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Shell Programming and Scripting

reverse the file content blockwise

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# 1  
Old 11-28-2011
reverse the file content blockwise
Hi,

I am having a file with some data present in blocks
e.g.

Code:
----------------
some data
some more data
couple of more lines.
----------------
another set of data
more lines
----------------
even more data
more lines
----------------

what I need is reverse the data.
like..
Code:
----------------
even more data
more lines
----------------
another set of data
more lines
----------------
some data
some more data
couple of more lines.
----------------

the number of blocks are NOT fixed.
the two blocks are separated by "----------"

Thanks.
# 2  
Old 11-28-2011
A little strange, but almost there...
Code:
$ cat sample10.txt
----------------
some data
some more data
couple of more lines.
----------------
another set of data
more lines
----------------
even more data
more lines
----------------

$ cat sample10.txt | sed 's/^\-/~\-/g' | tr "\n" "*" | tr "~" "\n" | tac | tr "*" "\n"
--------------------------------
even more data
more lines

----------------
another set of data
more lines

----------------
some data
some more data
couple of more lines.

# 3  
Old 11-28-2011
Open logic Shell script. The main issue with this file is the first line (which does not conform to the structure of the file). So we have to ignore it.

Code:
(
read junk       # Waste first record
while read line_01
do
        read line_02
        read line_03
        read line_04
        read line_05
        read line_06
        read line_07
        read line_08
        read line_09
        read line_10
        #
        echo "${line_08}"
        echo "${line_09}"
        echo "${line_10}"
        #
        echo "${line_05}"
        echo "${line_06}"
        echo "${line_07}"
        #
        echo "${line_01}"
        echo "${line_02}"
        echo "${line_03}"
        echo "${line_04}"
        #
done
) < input_file.txt

# 4  
Old 11-28-2011
Another try
Code:
$ cat sample10.txt
----------------
some data
some more data
couple of more lines.
----------------
another set of data
more lines
----------------
even more data
more lines
----------------

$ cat sample10.txt | sed 's/^\----------------/~/g'  | tr "\n" "*" | sed 's/~/~\n~/g' | tac | tr -d "\n" | sed 's/~~/~/g' | tr "*" "\n" | sed 's/~/----------------/g'
----------------
even more data
more lines
----------------
another set of data
more lines
----------------
some data
some more data
couple of more lines.
----------------

# 5  
Old 11-28-2011
Code:
gawk 'BEGIN{RS=ORS="----------------\n"}{a[NR]=$0}END{for(i=NR+1;i>1;--i)print a[i]}' infile

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